Liquid fuel burner



A rifl 3@, W35 w. E. TAFT LIQUID FUEL BURNER Filed April 15, 1929 2 Sheets-Sheet l April H3,

W. E. TAFT LIQUID FUEL BURNER Filed April 15, 1929 2 Sheets-Sheet 2 Jidwem ?@z Patented Apr. 3( 1935 STATES PATENT orris LIQUID FUEL BURNER Application April 15, 1929, Serial No. 355,066

11 Claims.

This invention relates to oil burners of the type having a base provided with annular fuel channels and perforated combustion tubes or chimneys which upstand above the base and sur- 5 round the channels and between which combustion of the liquid fuel vapor and gas takes place.

With the usual liquid fuel burner of this general type, a liquid fuel such as oil is maintained at a constant level Within the fuel channels and 10 is adapted to be continuously vaporized by the heat of combustion of the vapor in the space between the chimneys and above the channels. With this type of burner much trouble is experienced in the formation and collection of carbon in the fuel channels due to the breaking down or decomposition of the oilas it vaporizes resulting in the clogging of the channels and the fuel passages communicating therewith and necessitating frequent, as weekly, inspection and cleaning to maintain the burner in operative condition.

An objectv of the present invention is to provide an oil burner of the general type above set forth which is so arranged that it is practically free from carbon deposits so that it can remain in good operative condition for long periods of time.

A further object of the invention is the provision of a burner having an annular fuel chamber with combustion tubes or chimneys extended upwardly therefrom and so arranged that combustion of the fuel is caused to take place within the chamber and below the chimneys, thereby heating the walls of the combustion chamber to 35 such a high degree that vapor only can exist in the chamber.

In carrying out the above object of the invention, I provide an annular fuel chamber which is large in its radial dimension as compared with heretofore common practice. I also provide a cover for the major portion of the radial extent of the chamber leaving only an annular opening at one side of the chamber which is small in radial extent as compared with the radial extent of the chamber. Such construction is a further object of the invention. r

A further object of the invention is the provision of an oil burner havinga base provided with a plurality of radially-spaced, concentric, annular fuel channels with annular air passages between the channels and with an air passage within the innermost channel, and combustion tubes or. chimneys carried by the Walls of the channels and upstanding therefrom, the base having vapor passages which connect the concentric channels, the innermost channel being substantially larger in radial extent than the outer channels and receiving the fuel.

A further object of the invention is the provision of electrical high tension igniting means for the burner and especially means wherein the ignition electrode is removable from its operative position along with one of the combustion tubes.

Another object is the provision of electrical heating means for the burner and the fuel therein.

A still further object of the invention is the provision of mounting means having a plurality of burners of the type above described wherein the burners can be readily removed from operative position on the mounting means and restored thereto and held in a predetermined position without the necessity for employing set screws or bolts or special tools.

A yet further object is generally to improve the construction and operation of oil burners.

Fig. 1 is a side elevation, partly in section, showing a plurality of oil burners on a support ing mounting within a furnace.

Fig. 2 is a sectional elevation taken along lines 2-2 of Fig. 3.

Fig. 3 is a'plan view of the burner of Fig. 2, withall but the innermost combustion tube removed and with the cover of the innermost annular fuel channel broken away.

Fig. 4 is a plan detail of the supporting bracket for the burner.

Fig. 5 is an enlarged detail'showing a portion of the bracket and a burner and illustrating par- 5 ticularly the manner in which the burner is connected with the bracket.

Fig. 6 is a sectional detail, taken along lines B='| of Fig. 2.

As here shown, the burner includes an annular cast iron base It having an outer annular fuel channel or chamber 5 2 provided with radially spaced upstanding bounding walls M and i ii, and an inner annular fuel channel or chamber 98 which is concentric with said outer channel 12 and has upstanding radially-spaced side walls 2! and 22. The channels are integrally connected by a plurality of spaced ribs 24 which serve to hold said channels in radially spaced relation and also to provide an annular air channel 2% of substantial radial extent between the fuel channels. The ribs 24 are provided with horizontal, radially-extended ducts or fuel passages 28 which are of substantial cross-section andthe bottoms of which are substantially in horizontal line with the bottoms of the fuel channels I2 and I8 and serve to connect said channels in a plurality of points around the circumferential extents thereof. The annular wall 22 of the innermost channel l8 constitutes a neck which surrounds a large air opening or passage 30.

A vertical fuel pipe 32 is extended through the bottom wall of the base l9 and terminates substantially flush with or somewhat above the bottom of the innermost channel 58 adjacent the inner wall 22.

In accordance with this invention, the innermost channel or chamber 68 is considerably wider or of greater radial extent or width than, is usually the case and is greater in radial extent than the narrow outer channel IZ. A. removable cap or cover 34, composed of cast steel, has an annular recess 38 in its bottom face in which the upper end of the inner wall 22 is. received and on the top of which wall said cap is seated removably.. The peripheral edge33 of said cap extends downwardly into the open portion of the annular channel l8 and horizontally thereover and its periphery is located in spaced confronting relation with' the outer wall 20 of said channel i8, thereby to provide a narrow annular vapor passage 40. that communicates with the interior of said channel or chamber 98 and is. of considerably smaller radial extent or width than is said channel and is approximately as wide as the outer channel. the open end of the fuel pipe 32. The walls It, 56 and 28. and the peripheral edge 38;.of the cap 34 are provided with. seats 42 on whichverticallyupstanding concentric and radially-spaced combustion tubes or chimneys 4A, 45, 48 and 59, respectively, are seated removably. Said tubes thus form between them vertical annular combustion chambers 52' and 5% respectively which are located above and are in communication with the fuel channels I52 and i8, respectively. The tubes 56.- and 48; cooperate to provide an annular air chamber 5.52 which is; located between the adjacent combustion chambers. The combustion tube 58 surrounds the inner. air chamber 58 which receivesairthrough the neck 311' and the axiallyaligned passage 69 in the removable cap 34. Said tubes are perforated. throughout their axial and circumferential extent as, isindicated best in Figs. 1 and 5, wherebyiair. for combustion is drawn through the perforations into. the vapor or combustion chambersv 52; and 5.4:thr0ugh said walls. Acover plate 62 is disposed upon the top of the innermost combustion. tube 5d and has an outstanding ledge 64 that is seated on the end of said tube. Said cover 62. is connected by screws 56 with the cap 34 so that. said cover, tube and cap can be withdrawn as aunit, thereby freely exposing the inner fuel channel 18; A ring 68 is received within the tubes 46. and 48 and forms a closure for the top of the air chamber therebetween and has outstanding flanges H3 which overlie and are seated uponthe tops of saidtubes; Said latter tubes and said outermost tube M can also be removed from the burner. base upon need.

The outer periphery of. the cover 62 is not in continuous peripheral engagement. with the upper portion of the inner face of the tube 5d as it has been found that, with such continuous engagement, the expansionof the cover under heat permanently expands the top. of the tube. Consequently the cover is providedwith afew periphera ally. spaced projectionsfifia which engage the inner,- face of" the tubeat the top, there being clearance channels 53a betweenthe'proiections. Withthis Said cap 3.4' also overlies.

arrangement, when the cover is heated and expands, the top of the tube is forced outwardly at the projections and draws into said channels, between said projections. As a consequence, while the tube is temporarily distorted, the material thereof is not put under such great strain as to destroy it permanently and, when the burner is turned off andthe cover has cooled, the tube regains its cylindrical shape. The outer periphery of the cover-ring 68 is similarly provided with outstanding projections 69 which engage the inner face of the top of the tube 46, and clearance channels 69a between said projections, for the same purpose.

The burner base is supplied with fuel through the aforesaid pipe 32 which communicates, see Fig. 1, through a coupling 72 and a valve M, with a pipe it that extends to a float valve F8 that in turn is connected to the main oil tank 88. The float valve is set in such elevated position with respect to the burner that the. oil level therein comes about midway'up the height of the fuel channels l2 and E8 of the burner..

When the burner is first started in operation, oil is in both of said channels to the same level. When the device is lighted the heat ofv initial combustion serves to vaporize the oil in the channels and supply more power for combustion. With the usual type of burner wherein the channels corresponding to the channels both of about the same radial extent, as. the channel 52, oil remains continuously in. both channels and boils therein for so long. asthe' burner is in operation. Due to the continual presence and boiling, of the oil in. the channels, the oiliscracked and broken down. or decomposed and carbon is depositedin: the narrow channels, and especially in the innermost channel. With the construction here shown, however; this action does not take place. After the burner has been in operation for a short while, or until the parts have reached a constant, temperature, it is. found thatthere is no liquid oil present in. the channels 152'. and I8 and that there is strong combustion taking placeiwithin the channel 518 whichcauses the oil to vaporize immediately without depositing carbon. and that the temperature of the cap and the walls of the channel ifi'is too high to permit; either oil or carbon. toremain in the channel. The fuel vapors pass upwardly into the combustion chamber 54 and. also through. the passages 28. into the channel I2. and thence upwardly into the combustion chamber 52' and mix. with air therein. and are burned. The burning; in these combustion chainbers takes place more orless in. the usual manner. Inspection of burners in operationindicates that strong. combustion takes place and a relatively high temperature is generated under. the cap 3.4 and. in the channel l8; that the cap 34 must be; made of steel instead ofv cast iron as a cast iron cap has; its lip or peripheral portion 38'burned away in less than a week of service, the burning progressingfrom the lower face of the cap. It is considered; that the large width. of the channel l8 combined with thecap 34 which covers the major portion of the topof the channel is effective ininsuring combustion andfreedomfrom carbon deposition in the channel it. The passages 28.-are large in crosssecticn todistribute substantially uniformly in the outer channel 12: gases and vapors that are generated. by the combustion in. the channel. l8 so-that the supply of gas and vapor to both combustion chambersis practically the same;

The devicev is started in operation electrically:

I 2 and #8 are It is found by means of a high tension conductor or ignition electrode 82 which is carried by an insulating bushing 84 secured in the removable cap 34 and extended horizontally through an-opening in theinnermost combustion tube 50 and terminated in closely-spaced relation with the tube 43 so that a spark will jump from the outer end of said elec-- trode to: said tube, which constitutes the other terminal of the igniting means, thus to ignite the combustible vapor in the vapor passage. The inner end of said ignition electrode is spaced above and is in close proximity with the upper end of a fixed conductor 86 which is secured to an insulating plate 88 carried by the burner base. Said conductor 86 is connected to one terminal of a suitable high tension transformer (not shown) while the other high tension terminal of the transformer is grounded onto a part of the burner. Since the high tension conductor 85 is not permanently connected with the ignition electrode 82, said electrodecan be removed from the aforesaid relation along with the cap 34 and the associated combustion tube 50.

Thefuel in the burner can be initially vaporized by means of an electric heating unit 99 in the form of a fiat disc having metal walls which enclose'the heating element, which unit is received upon the bottom wall 92 in heat-conducting relation therewith and under the inner fuel channel I8. The heating unit is held removably in the aforesaid relation by clips 94 which underlie said unit and are secured removably to lugs 9t which depend from the bottom-wall of the burner base. The heating unit is required to be in operation only long enough to vaporize oil for initial combustion and can thereafter be placed out of service.

Means are provided tosupport a plurality of burners within a furnace. Figs. 1, 4 and 5 illustrate supporting means for three burners. The supporting means includes a base 98 having feet um which are provided with leveling screws I02. A vertical shaft I04 upstands above said base and a supporting bracket I06 is slidable thereon and can be secured in any adjusted position thereon by screws I08. Said bracket I06 is provided with a plurality of, and, as here shown, three equiangularly-spaced upstanding bosses Hi] which have vertical passages I I2 therethrough.

The base III of each burner is provided with a depending cylindrical lug H4 which fits within the passage I I 2, whereby the burner is supported removably in position. The boss I I4 on the upper end thereof is provided with a laterally-extended lug or key H6 which fits into a horizontal slot II 8 in the top face of the boss III) thus locking the burner in fixed position against rotation. The slots are so arranged that, for the supporting bracket here shown, the burners are positioned equi-angularly apart.

The construction can be modified without departing from the spirit of the invention. For instance, the number of annular fuel channels can be increased, upon necessity, and need not be restricted to two as here shown.

I claim:

1. In a liquid fuel burner, a base having spaced upstanding side walls providing between them an annular fuel chamber, a cap removably seated upon the inner side wall, spaced combustion tubes carried respectively by the cap and said outer side wall and upstanding above and in communication with said chamber, a high tension conductor carried by and insulated from said base, and an insulated high tension electrode carried by said removable cap having one end there of disposed adjacent but free from connection with said conductor and having the other end extended through the combustion tube carried by said cap and into the space between said tubes and "terminating in spaced relation with said other combustion tube.

2. A combustion tube burner having a base provided with a fuel channel, spaced perforated combustion tubes in upstanding relation to the base forming between them a combustion chamber having an air supply through the perforations in said tubes and opening at itsbottom into said fuel channel, means to supply liquid fuel to said channel, electrical heating means associated with said base but out of contact with said liquid fuel to preheat and vaporize said fuel by conduction through the Walls of the base, and electrical igniting means to ignite the fuel vapor comprising a spark creating device immediately above said fuel groove within and near the bottom of said combustion chamber and within the region of the air supply thereto.

3. A combustion tube burner having a base provided with a fuel channel, spaced perforated com-' bustion tubes in upstanding relation to the base forming between them a combustion chamber having an air supply through the perforations in said tubes and opening at its bottom into said fuel channel, means to supply liquid fuel to said channel, electrical heating means to preheat and vaporize the fuel in said channel, and electrical igniting means to ignite the fuel vapor comprising a spark creating device in the combustion chamber within the region of the air supply thereto.

4. A combustion tube burner having a combustion chamber, a base provided with a vaporizing chamber communicating with said combustion chamber, a removable cover for said vaporizing chamber, and an electrical, fuel-igniting device supported by said cover.

5. A combustion tube burner having a base provided with a vaporizing chamber, means for supplying fuel to said vaporizing chamber, a removable cover for said chamber, and fuel igniting means comprising an electric, current-carrying device supported by and removable with said cover.

6. A burner having a base provided with an annular fuel channel, spaced, perforated combustion tubes in upstanding relation to the base and forming between them a combustion chamber above and communicating with the fuel channel, a structure removably resting on the walls of the base interposed between the latter and one of the combustion tubes but providing a support for said tube, and electrical, fuel igniting means including a current-carrying member carried by said structure.

'7. A burner having a base provided with an annular fuel channel, combustion tubes in upstanding relation to the base and forming between them a combustion chamber above and communicating with the fuel channel, electric, fuel igniting means including an igniting member positioned immediately above the fuel channel, a structure removably seated on the base and carrying said igniting member, a fixed terminal for said member carried by the base outside of said annular channel, and a cooperating and registering movable terminal carried by and movable with said structure whereby, when said structure is applied to the base, said movable terminal is operatively related to said fixed terminal. V

8. In a liquid fuel burner, a base having outer and inner spaced upstanding side walls providing an annular fuel channel therebetween, means to admit fuel to saidchann'el, a cap seated removably upon said base, combustion tubes carried by said cap and said outer wall respectively on. opposite sides of and upstanding above the top of; said channel, an electric igniting member carried. by said removable cap and. located inthe space between thev tubes, a fixed terminal for said member,. and a cooperating movable terminal carried by and removable with said cap.

9. A combustion tube burner having a base pro:- vided with an annular fuel channel, said burner having a combustion chamber above and communicating with the fuel channel, a structure removably resting on the walls of the base, and fuel igniting means comprising an electric current-carrying device carried by said structure and positioned in said combustion chamber immediately above said fuel channel.

10: A combustion tube burner having a base provided with an annular fuel channel, spaced perforatedcombustion tubes removably supported in upstanding relation on the base. forming between them. a combustion chamber provided with arr air supply through perforations in said tubes and opening at its bottom into said fuel channel, and electric fuel igniting means including an insulated electrodeand means structurally uniting. the same with one of said tubes and rendering it removable therewith, said electrode being positioned insaicl combustion chamber above the lowermost perforations in said tubes and in the region of air supply to said chamber, said burner presenting a companion electrode in spaced relation to said first electrode.

11. A. burner having a base provided with an annular fuel channel, removable combustion tubes in upstanding relation to the base and forming between them a combustion chamber above and communicating with the fuel channel, fu'el igniting means including an electrode projecting through but insulated from one of said combustion. tubes and means structurally uniting said insulated electrode with saidtube, rendering it removable therewith, said electrode being positioned in the space between saidtubes, a companion electrode presented by the burner, a fixed terminal-carried by the base for said first named electrode and; positioned so that when said tube is positioned on the base, said first named electrode is operatively related to said fixed terminal.

WILLIAM EDWARD TAFT. 

